Tag Archives | fibreglass

Milling Machine Bench and Workshop Update

I’ve recently acquired a couple of significant additions to my workshop so I thought it was about time I did a workshop update post.

These two new additions are one Sieg SC4 metal lathe and one Sieg SX3 milling machine. The latter of these two weighs 165Kg (363lb). I didn’t like the idea of having to move this machine more than once so I thought it was appropriate to build a sturdy bench on castors which I could put the machine straight onto upon receipt.

The SX3 Mill is also sold is a Grizzly G0619

I got these machines through Sieg Machines New Zealand. They stock and source a wide range of machines and accessories. Chris the owner has been very helpful. Check them out at www.sieg-machines.co.nz

 

As with most of my projects, the bench ended up being needlessly over engineered! I conclude that I have Inceptionitus. I.e. Once an idea has taken hold of the brain it’s almost impossible to eradicate’.

In this case the idea stemmed from the thought that eventually I would convert this milling machine to CNC therefore I’d want a way to contain swarf and cooling fluid. Initially I considered forming a tray using some kind of rubber lining like butyl rubber membrane, but I was concerned about chemical resistance.  Then it occurred to me that a moulded fibreglass tray would be a ‘simple’ solution to the problem. And that was it, the idea had taken hold. Of course it’s much easier to conceive an idea than to complete a project! Let’s begin…

 

First step – Get the dimensions of the machine and create designs in Sketch-up.

TrayMold

Mould design for the fibreglass tray (Inverse of the final product)

 

 

BenchDesign

Overall bench design

 

I decided to make the fibreglass tray first so that I could adjust the bench design to accommodate for any inaccuracies in the fibreglass which once set can’t be adjusted.

 

The mould was made from:

  • 9mm melamine board
  • Scraps of cupboard door chipboard laminate
  • 20×45 Pine cavity batten
  • Plasticine
  • Duct tape
  • Polyester builders/auto filler
  • 6mm MDF

 

MouldMaking2

MouldMaking3 MouldMaking7MouldMaking5  MouldMaking10

 

This was a stupid way to make the drain hole. If I did it again I’d use the top section of a soft drink bottle or similar.

DrainMaking DrainSand

DrainDone

 

I did a few test pieces of fibreglass to get a feel for the gelcoat which I hadn’t used before. And to work out the best tape to use. I found that the resin sticks least to the duct tape. Masking and packaging tape were also fine but the heat from the curing process made them wrinkle.

GelcoatTests

 

Plasticine is used in the corners to give a radius. Fibreglass doesn’t like bending at 90 degrees.

MouldPast

 

I put tape over the plasticine on the long stretches because it gives a nicer finish than the plasticine.

MouldDone

 

Two coats of gelcoat brushed on with a a couple of hours between coats and left to cure for a few hours.

GelcoatDone

 

After the gelcoat I laid down a single thin layer of fibreglass re-enforcing with polyester resin and allowed it to fully cure and then sanded it. Doing this (as opposed to adding multiple layers straight away) significantly reduces the chance of getting air bubbles between the gelcoat and the fibreglass.

After this three more layers of resin and chopped-strand-mat reinforcing was added. I ended up with a few air pockets in these layers but nothing too major. Perhaps I should have let each layer to set up at least a little before adding the next.

FibreglassDone

 

Edges cut flush with a diamond blade on the angle grinder then smoothed off with a normal disc.

MouldGrind

 

I naively thought I would be able to remove it from the mould without disassembly. Yeah right!

MouldDissasembly

 

TrayDone

As expected there are lots of moulding artefacts but overall I’m very happy with it. Especially considering it was a fairly rushed job over one weekend and a few week nights.

MouldingArtifacts

 

Now on to the bench itself…

The bench design is based on the same torsion box design as my main workshop bench.  Pretty overkill but I still had a lot of plywood offcuts from the workshop restoration that I needed to use up.  There are castors on each of the four corners rated at 280Kg each. The centre foot jacks down with three 16mm bolts.

Bench1

Bench2

 

Bench2-1

 

I was able to recycle wood from the fibreglass mould to make the fixing blocks for the bench top.

Bench3

Bench3-1

Bench4

 

I used auto filler on the rough edge of the tri-board to give it a smooth seald finish.

Bench5

 

And now for the best part…the install.

Finals3

 

Finals4

Finals1

 

Finals5

On the left: Sieg SX3 milling machine. On the right: Sieg SC4 lathe

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Thanks

Special thanks to my wonderful wife who painted the bench, to Simon for the help and use of the engine crane. And to Andy for the offer of the engine crane. To Chris at www.sieg-machines.co.nz for all the help. And to Adam who transported the machine.

And a plug for my favourite local businesses:

NZ Fibreglass, always with helpful advice and Hill Lumber who have the best lumber prices around

 

Conclusion

Things I’d do differently:

  • Contouring the tray and drainage area to make sweeping swarf away easier
  • Take more care on the mould to reduce the moulding artefacts
  • I’d consider making a reusable fibreglass mould so I could make more trays and sell them – although I suspect the market in NZ is fairly small
  • I probably wouldn’t bother with the jack’able middle leg and just use casters instead. The cost of the large bolts wasn’t much cheaper than the casters in the end. Arguably it provides more strength to the structure right under the machine. Arguably the middle leg is overkill and not needed at all!

Thanks for stopping by, hopefully this gives you some ideas if you’re thinking of doing something similar.

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Fibreglass CPU Duct for a Quiet Home Theatre PC

"Don't breath this"New Zealand Freeview has just launched it’s high definition DVB-T TV service and my existing HTPC was nowhere near up to spec for decoding the high def streams. It was also too noisy for a computer that lives in the lounge so it was time for a rebuild. I was pretty excited; this is my first brand new PC in about 10 years the last one was a Pentium 120 when I was still at school! Of course I’ve had plenty of second-hand and hand-me-down gear between then and now.

The two main requirements for the new build were enough power to decode high definition video and quiet enough not to drive me crazy. Quiet means efficient cooling, I.e. good air flow.

I wanted to run the fan at very low RPM while maintaining good air flow across the CPU and video card; the idea is to pull air past the passively cooled video card, though the CPU heat sink and vent it straight out the back of the case.

I could have hacked a duct together with cardboard and tape but that would been just too easy, besides I wanted to try my hand at some fibre-glassing. After much research, trial and error Here are the basic steps I went though.

Materials (Fibre glass bare essentials can be had for about NZ$50)

  • Polyester resin
  • Methyl ethyl ketone peroxide (MEKP – The catalyst used to harden the resin)
  • Fibre glass re-enforcing Chopped strand Matt (CSM)
  • Polyvinyl alcohol release agent (Used so you can separate your part from the mold)
  • Release wax
  • Acetone (For cleaning up)
  • Cheap bushes
  • Mixing containers
  • Latex gloves. (Keep the nasty chemicals from burning your skin, Box of 100 – you have to change them often)
  • Stirling sticks
  • Respirator mask
  • Casting plaster to make the mold (Not used in the end. See trial and error!)
  • Wood, plywood, tape, misc tools, sandpaper, etc etc

Thanks goes to NZ Fibreglass. They were very helpful; they sell in small and large quantities and took me though exactly what I needed to get started so if your in Auckland and need fibreglass gear it’s the only place to go check them out at:
http://www.nzfibreglass.co.nz/

Materials

1. Make a mold from wood (and masking tape!).

Basic Mold

2. Coat the mold with resin and some fibreglass re-enforcing where strength and shape is needed, around the corners and over the masking tape.

Mold Coated with Resin

3. Sand the resin coated mold very smooth

Cleaned and Polished Mold

4. Wax the mold with release wax; about 6 coats, till it’s very shiny.
The guy at the fibreglass shop was very kind and gave me the last of a tin of wax they had in their workshop; saving $30

Waxed Mold

5. Brush on polyvinyl alcohol release agent. This stuff is great, it forms a sort of plastic bag-like skin so you can release from the mold. It should really be sprayed on evenly with a proper spraygun but this will have to do.

Brush Mold with Release Agent

6. Now ready for the first layer of fibreglass. Mix up the polyester resin with the hardener. Soak the resin into the glass with a dabbing action too much brushing and the fibres will start to be dragged around with the brush. The glass should be saturated and become transparent.

Mix Resin and HardenerFirst Layup

The first layer is done!

First Layer Done!

7.Now the moment of truth; separate the part from the mold?

Separate the Piece from The Mold

Note the PVA film has formed a barrier between the resin and the mold.
At this point I’m wondering if the wax was really necessary.

10separate-medium

The part released reasonably cleanly

Part separated from mold

8.Add more re-enforcing and a top coat of very thin glass tissue. (My homemade roller helps get out air bubbles)

Fibreglass Tissue Finish

9. Clean-up (sand), add holes for top of heat sink

Mold Sanded and Cleaned

10. Add bottom sections

Bottom Section Added to Mold

11. Lots of sanding to get it nice and smooth and ready for painting

Lots of sanding to prepare for painting

12. Into the “spray booth”….

In to the Spray booth

…Prime and paint

Prime

13. Done!

Done

Thermalright Heatsink

Duct Instlled (Far)

Duct Instlled (Near)

Full System Specs

  • Motherboard: Intel DP35DP Media series
  • CPU: Core2Duo E8400 3.0Ghz 45nm
  • RAM: 4GB Crucial
  • Video: Passively cooled Nvidia 8600GT (Gigabyte SilentPipe II)
  • Hard drive: Seagate 320GB SATA
  • Power supply: Enermax liberty 400(watt)
  • Case: Lian li PC61 (Big thanks to Chris for this very nice all aluminium case)
  • CPU Heatsink: Thermalright Ultra 120 Extreme
  • CPU Fan: Yate Loon D12SL-12 (700RPM @5 volts)
  • TV Cards:
    • Satellite (DVB-S)
      • Technisat SkyStar 2 (PCI)
      • Technotrend S1500+CI Module (PCI)
    • Terrestrial (DVB-T)
      • Hauppauge HVR-2200 Hybrid Dual Turner (PCIe)
    • Analog
      • Hauppauge PVR-150 (PCI)
      • Hauppauge HVR-2200 Hybrid Dual Tuner (PCIe)

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